<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
    <style>
    /* 将p标签属性为bw1的变为绿色 */
    p.bw1{
        color: green;
    }
    /* bw1.p{    //要大的范围在前面
        color: red;
    } */
    </style>
</head>
<body>
    <p class="bw1">ppp</p>
    <p class="bw1">ppp</p>
    <div class="bw1">div</div>
    <div class="bw1">div</div>
    <p>ppp</p>
    <p>ppp</p>

</body>
</html>